Modeling The Pediatric Upper Airway Using Anatomic Optical Coherence Tomography and Computational Fluid Dynamics (DNS) Project Summary Upper airway obstruction is a problem that affects up to 3% of all children. The problem is multifactorial and includes both anatomic and neuromuscular elements. The most common cause of upper airway obstruction is related to adenotonsillar hypertrophy. Adenotonsillectomy (AT) is among the most common operations performed the United States with about 600,000 children undergoing AT each year. AT results in significant improvement in relieving symptomatic airway obstruction in the vast majority of children;still large numbers of children do not benefit from this treatment and this is particularly true in children with craniofacial anomalies, Down's syndrome, and obesity. Identifying children who fail to respond to AT prior to surgery is exceptionally challenging. This proposal is in response to the RFA-HL-10-017 and aimed at developing and validating new modeling and in vivo measurement tools for evaluating/predicting upper airway dysfunction in children. The integrated multi-center international team will focus on the development of computation models using direct numerical simulation models for airflow to identify the biological and structural components creating airflow limitation in the pediatric upper airway. To provide in vivo structural data for modeling, we will develop high speed Fourier Domain mode locked swept laser based anatomic OCT (FD-A-OCT) system to achieve real-time 3D imaging of up airway. The broad long-term objective of this proposal is to develop DNS driven simulations of upper airway airflow in tandem with high-speed 3D FD-A-OCT as a means to: 1) image upper airway anatomy in awake children;and then 2) simulate the flow of air in the upper airway to gain information on flow, pressure, and turbulence. This model development and in vivo measurement technology aims to ultimately improve accuracy in selecting patients for and predicting the response to surgery. This proposal integrates expertise in optical coherence tomography (Chen), device design (Wong), computational fluid dynamics (Elghobashi, Pollard, Kimbell), and clinical expertise (Wong, Rhee, Ahuja) to develop a system to generate real-time 3-D volumetric images of the internal airway structure and estimate airflow dynamics in children. The structural information on internal airway anatomy will allow simulation of upper airway airflow and estimation of the impact of surgery on relieving airway obstruction. In turn, the model will provide a means to determine which children will benefit from upper airway surgery, and is a first step toward developing individualized surgical therapy. The development and rapid translation of patient specific geometry to CFD modeling, will set the stage for pre-surgical planning/interventional surgery. PUBLIC HEALTH RELEVANCE: Project Narrative Upper airway obstruction is a major problem in children, and identifying the anatomic location of airway collapse is difficult. Development of an office-based treatment technology to image the upper airway in awake children, and then compute airflow accurate would decrease morbidity and reduce health care costs. (End of Abstrct)